Shower wall water infiltration: Will dehumidifier help?
One of the shower stalls in the apartment/condo was inspected by the home inspector and mentioned to have "water infiltration" (measured by the moister meter) behind the wall's ceramic tiles. He mentioned that water has probably dampened the wall behind the ceramic tiles, since the grout wasn't properly sealed.
Will it be possible to fix this by putting a heavy-duty dehumidifier + fan inside the shower stall for a week or so? Then seal the grout to prevent any additional water from penetrating behind the tiles.
There are several problems here. 1). If the walls are truly damp behind the tiles, they may have already been damaged depending on the wall construction. 2). Running a dehimidifier will take forever to dry out anything behind the tiles. Drying out walls involves forcing dry air into the wall to drive moist air out. The equipment to do this is very specialized. 3). Did the inspector use a probing type meter to investigate, or a surface type meter? Surface type meters are not very rteliable on tile walls. Grout can hold moisture from the last time the shower was used and give a false reading. Also certain tiles contain oxides in the pigments that can fool a surface reading meter. Someone testing tiles with a surface reading meter needs to be very careful with their technique. I've actually witnessed guys taking high readings on tile walls that were absolutely dry when measured on the backside of the wallboard. If possible, access the wall cavity and inspect and test from the back side.